1 : one who insists on exactness or completeness in the observance of something a stickler for the rules.

Who is stickler for the rules?

Stickler has its origins in a word meaning umpire, which may allude to a stickler's bossy nature. Difficult problems or puzzles are called sticklers. It is helpful when remembering the definition of stickler that it has the word “stick” in it. So someone who “sticks” to the rules is a stickler.

Who is an insisting person?

ĭn-sĭstənt. The definition of insistent is demanding or persistent. An example of an insistent person is someone who keeps giving support for a lie, no matter how many times he is questioned or proved wrong.